Lubrication of slide-valve internal combustion engines



Jan. 16, 1940. R. L. 'sKlNNl-:R 2,187,235

LUBRICATION 0F SLIDE-VALVE INTERNAL COMBUSTION ENGINES ATTORNEY.

` Jan. 16, 1940. f V R. L. sKlNNl-:R 12,187,285.V

LUBRICATIO OF SLIDE-VALVEJINTERNAL COMBUSTION ENGINES Filed sept. 19,V 1958 2 sheets-sheet 2 INVENTOR.

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ATTORNEY.

f UNITEMTA PATENT;:oFFrcE^ sav-f mavxnvmmmrwj Ralph L. Skinner, sDetroit,` Mich.,fassignor to SkInnerMotormJnc., Detroit, Mich., acoro.` l A ,ration of Delaware {Apucaan sepenlaer 19,1938, seriamolggaoscs e 9 claims. l (oi. 1miissy` 'Inejpreseht invention rlatestd internetgembustion vengines and comparable structures of p the sleeve-valve or `slide-valvetype and itis designed more particularly to reduce the' yoil con- `sumption without the employment off ,complicated devices for removing excess `oil from the surfaces of` the valves `and from the spaces in which the Valves operate.

`This aim is desired, because of the fact'that, `inthe past, engines using slide-valves or` sleeve- A valves, either of the single-sleeve or double-sleeve type, have consumed more lubricating oil than poppet-valve` engines` of similar size and per- Iormance and this fault, heretofore, has-been overcome only through the use of relatively complex devices for mechanically scraping the oil from the surfaces of the valves or for removing the lubricant from the valves by means of vacuum or sub-atmospheric pressure.

In an engine structure incorporating the present invention in its latest or current preferred embodiment, the oil consumption of'slide-valve.

or sleeve-valve engines is greatly reduced by the Vsimple meansof making the valves themselves operate as air-pumps andusing the air pumped by such valves to blow or expel the excess oil from the surfaces of thel valves back into the engine crankcase.

In the approved form of the invention, as incorporated in a slide-valve internal-combustion engine of the type presented in Patent No. 1,830,136, a .hole is provided in the exhaust side of the cylinder-bore near the top of the cylinder in such a position that the port thus provided is alternately opened and closed by the exhaustvalve itself, and, while thisport can be open to the atmosphere, it is preferable to connect it through a suitable conduit with the crank-case of the engine to prevent the entrance of outside dust and dirt.

The position in the cylinder at which this port is supplied ls such that the exhaust-valve covers and closes it during at least-a portion of the time when both valves are moving toward the top of the cylinder, whereby they force out the air and oil beyond them, and the. exhaust-valve uncovers and opensA such port during lat least a portion of the time both valves are moving conjointly downwardly or away from the top o! the cylinder.

Since, due to the normal operation of the engine, the exhaustvalve goes through its cycle of operation ahead of the intake-valve, it will be apparent that the exhaust-valve -will close this port in the cylinderwhile the intakevalve isnear its lowest position, and,"after` such port'is thus covered or closed, both valves rise' toward the top of `the cylinder and tend to compress the air that is trapped in the space between the tops` of the valves andthe head of the cylinder.

The air tended to` be compressed in this annular space has an available exit down the cylinder through the spaces between the edges oi the two valves, and in passing down through such spaces, the' air carries with it lubricating oil which 1* would otherwise be present in, or find its way to, the top of the cylinder and into the combustion-chamber causing smoking of the exhaust.'

Later, in the cycle of operations,` the exhaustvalve having passed its top position moves downwardly and uncovers the port in theside of the' cylinder, this occurring at a time when the intake-valve is near the top of its stroke.

Then, as both the intake and exhaust valves move downwardly simultaneously in the cylin- 20 der, they tend to create a vacuum in the annular space between the head of the cylinder andthe upper ends oi.' the valves and air enters this space through this port in the cylinder-wall to occupy the space vacated by the valves, thus preparing 25 for a repetition of the cycle so that the next time the exhaust-valve rises and closes the port ferred to preventing the creation o1 a vacuum therein which would otherwise detrlmentally suck excessoil into such space.

For use in a Knight-type or double-sleeve en- 85 gine, the principle is exactly the same, although the construction is slightly different, two alternative methods being possible of satisfactory employment, the simplest 4consisting of merely a port in the cylinder block at the correct height 40 in the cylinder anda'lso a port in the outer sleeve f the valve-mechanism so placed that it will at times register with the port in the. cylinder-block,

by this method making it possible to create'considerable air pressure in the annular space at the top of the cylinder.

In order to use to best advantage the pressure thus created, grooves can be cut in either or both of the valve-sleeves in such a manner that the compressed air at the top of the cylinder blowing down through these grooves will return the excess oil on the surfaces o! the sleeves to the crank- Case.

Regarding the single-sleeve or Argyle-type of engine, two small grooves are out on the outside 5.5

of the valve-sleeve, both of crescent-shape and lation, if desired.

both extended to .communicate with the annular space between the top of the valve and the head of the cylinder, one o! these grooves being convex to the right when viewed from the outside-oi thesleeve and the other convex to the left, the top of each groove being on the same element of the `valve-sleeve as the bottom of such groove;

When suchvalve-sleeve isl at the bottom of its stroke and starting upwardly, a port in the cylinder-block which connects with grooves in the cylinder-block and valve-sleeve or both, is in register with-one of the crescent-shaped grooves on the outside of the valve-sleeve, and, as the valve rises in the cylinder, it tends to compress the air above it and to create a pressure in the annular space between the top of the valve and the head of the cylinder. r

The only available outlet for this -air is through this crescent-shaped groove and the port with which it is in register and thus through the oil- -scavenge grooves to the crankcase, and, when the valve has reached the top of its stroke, its rotary motion causes this crescent-shaped groove to pass out of register with this p'ort, and, at the same .time, causes the other crescent-shaped groove to come into register with another port in the' cylinl der-wall. This second port is connected either to the outside air or to-the crank-case and the downward motion of the valve-sleeve tends to create a partial vacuum in the space between the top of the valve and the head of the cylinder, thus causing air to be drawn in either from the outside atmosphere or from the crankcase through the second crescent-shaped groove and the port with which it is in register.

At the bottom of, the valve-stroke, the process is reversed and the crescent-shaped groove -on the suction side passes out of register with that hole while thecrescent-shaped groove in the pressure side comes into register with its outlet port.

lOne outstanding valuable feature of the constructions referred to is that the motion of the valve or valves is used to produce a movement of air that can be utilized in diminishing the specinc oil consumption of the engine, but, it is to be understood that, instead of using the slide-valves or sleeves as a pump, a separate air-pump can be employed if desired on any of the types of engines mentioned.

A subsidiary valuable characteristic of the novel and improved construction is that it eliminates the necessity for using any scraping devices or vacuum suction mechanism for the removal of the oil from the valves and that it can also be employed for controlled crank-case venti- To permit those acquainted with this art to fully understand the invention, a present preferred embodiment thereofas applied to a slidevalve internal-combustion engine, has been illustrated in the accompanying drawings, and, for simplicity, like reference numerals throughout the views have been used to designate the same parts and--an understanding of this construction will make it clear to those trained. in this art how the `invention may be satisfactorily employed in Knight or Argyle type of engines.

lIn these drawings:

Figure 1 is a partial, central, longitudinal secythe broken 'line 2-2 of Figure 1.

By reference to these drawings, it will be perceived that each jsection of the multi-cylinder engine includes anouter, water-jacketed cylinder Il, a shorter, inner cylinder I2, inside of, concentric with, and spaced inwardly away from the outer cylinder, a piston I2 reciprocatory in such inner cylinder and a connecting-rod Il op- 5 eratively joining the piston to the usual crankshaft I5.

In addition, the engine for each such cylinder includes -a split, ported sealing-ring I1, seated on the upper end of the inner cylinder, having ports in register with the intake and -exhaust .ports Il and Il, respectively, of the outer cylinder, a hold-. down ring 2l bearing on the sealing-ring, circular reeds 22 mounted on the cylinder-head 2l and pressing against the inner face of the ring 2 l, and coiled springs 24, 24 mounted in the cylinderhead and pressing down on the ring 2 l the cylinder-head being equipped with the usual sparkplug 26.

Between such other cylinder,`on the one hand,

land the .inner cylinder. sealing-ring and holddown ring, on the other hand, are the two, ported, semi-circular, inlet and exhaust valves 28 and 21, respectively, and, in this particular engine, all of these curved slide-valves are reciprocated by 25 their individual connecting-rods 28 joined thereto and operated by a single crankshaft 29 along the side of the engine and driven from the main crank-shaft by means not necessary to illustrate.

Asis customary in this and other styles of 30 engines, the valves are lubricated by the splashed oil in the crank-case, or otherwise.

So far as now described, the structure does not incorporate the present invention, which involves a port Il through the cylinder-wall at the position indicated in Figure l, which opening .is desirably, but not necessarily, connected to the engine crank-case by a pipe or conduit 32.

From what precedes, it will be apparent that the reciprocation of the exhaust-valve 21 opens and closes port 3l.

For at least a portion of the time that the two valves are descending' conjointly, port v3l is open to prevent the development of any vacuum or sub-atmospheric pressure in the annular space 4- 'above the tops of thel valves between the outer possibly to some extent down the curved faces of the valves, and such dischargedI air carries along with it a certain amount of lubricant and delivers it back down the cylinder into the crankcase, which oi1,'f not thus gotten rid of from such space, would flnd its way int the combustion-chamber where it would be uneconomically burned or destroyed. Thus, for each complete reciprocation of the pair of valves oil in some measure is discharged from the space referred to, the valves themselves constituting a pump to effect this desirable result. As has been suggested, the air drawn in through the pipe need not be derived from the crank-case, but by connecting such tube to the crank-case an effective ventilation of the latter is assured and the possibility of dust being taken into .the mov- 7( ing parts of the engine is largely eliminated.

Again, instead of employing the sliding valve `or valves as an air-pump for the purpose indi- 2,187,285 Those acquainted with the art of internal-comL4 bustion engine lubrication will readily understand that this invention is not necessarily restricted and limited to the details of structure described 5 and illustrated and that the construction may be modified within reasonable limits without departure from the heart and essence of the invention as defined by the appended claims, which should be construed as generically as permitted by the prior art, and without the loss or sacrifice of any of its material benefits and advantages.

Whereas no speciiic means, other than the splash occasioned by the connecting-rods, has been shown in the drawings for lubricating the sliding-valves referred to, it is to be understood that any other or supplementary means may be employed for effectively `oiling the valves.

In the preferred construction referred to above, the port is opened and closed by the reciprocating exhaust-valve, but such opening may be lo- 'cated to be thus controlled by the intake-valve rather than the exhaust-valve.

I claim: l. In an internal-combustion engine, the com- 2l bination of an outer cylinder, an inner cylinder inside of andV spaced inwardly concentrically away from said outer cylinder, a head for and projecting into said outer cylinder, valve-means reciprocatory between said cylinders and in the 30 space between said outer cylinder and said head, means to reciprocate said valve-means, means to lubricate said valve-means, and means to admit air into and to circulate it through said space beyond the end of said valve-means and to dis-A pheric pressure thx'oughthe clearances of the valves and associated parts to remove the accompanying excess lubricant from said space.

2. The engine structure presented in claim l connecting with said space and opened and closed by said valve-means, whereby when said port is closed said valve-means ascending acts as a pump to expel the air and accompanying excess lubricant from said space.

3. 'I'he engine structure presented in claim 1 Y charge it from said space undersuper-atmosv in which said circulating-means includes a port 4. The engine structure presented' in claim 1 in which said circulating-means includes a port connecting with said space and opened and closed by said valve-means, whereby when said port is closed said valve-means ascending acts as a pump to expel air and accompanying excess 1ubricant from said space and when said port is open and said valve-means descends, the vacuum which would otherwise tend'to be created in said space is broken, avoiding drawing an excess of lubricant into said space. Y' 5. The engine structure presented` in claim 1 in which said circulating-means includes'a port connecting with said space and opened and closed by said valve-means, and a'condit connecting lsaid port with the engine crank-case, whereby when said portis open and said valve-means de.-

vscends, the vacuum which would otherwise tend to be created in said space is broken, avoiding drawing an excess of lubricant into said space, and when said port is closed said valve-means ascending acts as a pump to expel the air and accompanying excess lubricant from said, space.

6. In an internalecombustion engine, the ccmbination of an outer cylinder, an inner concentric cylinder spaced from said outer cylinder, a head for and projecting into said outer cylinder, inlet andexhaust' valves reciprocatory between said cylinders and in the space between said outer cylinder and said cylinder-head, means to reciprocate said valves, and means to lubricate said valves, said space having a vent-port opened and closed by the movements of one of said valves, said port being open during at least a portion of the'simulta'neous descent of thevalves, whereby air may then enter said space, said port being closed during at least a portion of the concurrent ascent of said valves, whereby air and excess lubricant are expelled from said space through clearances of the valves and associated parts.

7. The engine set forth in claim 6 in combination with a pipe connecting said vent-port to the interior of the engine crankcase.

8. The engine set forth in claim 6 in which the valve opening and closing said vent-port is the exhaust-valve.

9. The engine set forth in claim 6 in which the valve opening and'closing said vent-port is the exhaust-valve, in combination with a pipe connecting said vent-port to the interior of the engine crank-case.

- RALPH L. SKINNER. 

